Electrostatic recording apparatus for high speed operation

ABSTRACT

An electrostatic recorder as driven at a specific low speed to record information on a continuous sheet of recording paper. A developer and fixer is simultaneously driven at a specific high speed to develop and fix recorded information on the recording paper after the recorded paper is cut upon passing through the recorder.

United States Patent Sato [ 51 May 23, 1972 [541 ELECTROSTATIC RECORDING APPARATUS FOR HIGH SPEED OPERATION [72] Inventor: Tadakazu Sato, Yokohama-shi, Japan [73] Assignee: Fujitsu Limited, Kawasaki, Japan [22] Filed: Aug. 27, 1969 [21] Appl. No.: 853,376

[30] Foreign Application Priority Data Aug. 30, 1968 Japan ..43/63483 52 us. Cl ..346/74 Es, 346/74 CR, 355 13,

355/28 51 Int. Cl. ..G03g 15 00, 003 15 22 [58] Field of Search ..355 28, 13; 346/74 ES, 74 CR [56] References Cited UNITED STATES PATENTS 3,155,022 11/1964 Schwertz ..346/74 ES 3,382,783 5/1968 Chen ..355/28 3,472,687 10/1969 Masuda ...346/74 CR Primary Examiner-Howard W. Britton Att0rneyCurt M. Avery, Arthur E. Wilfond. Herbert L.

Lerner and Daniel J. Tick ABSTRACT An electrostatic recorder as driven at a specific low speed to record infonnation on a continuous sheet of recording paper. A developer and fixer is simultaneously driven at a specific high speed to develop and fix recorded information on the recording paper after the recorded paper is cut upon passing through the recorder.

2 Claims, 4 Drawing Figures PATENTEDMAY 23 we a. 665 486 V min 3 [1F 4 BR Z02 PATENTEDmzs 1972 3. 665 486 I sum v, pr-g ELECTROSTATIC RECORDING APPARATUS FOR HIGH SPEED OPERATION DESCRIPTION OF THE INVENTION The invention relates to electrostatic recording apparatus. More particularly, the invention relates to electrostatic recording apparatus for high speed operation.

Electrostatic recording apparatus or photographic facsimile apparatus has recently been widely utilized as an output device of an electronic computer or a peripheral device of a data communication system, since such apparatus has a high speed of operation or printing. In conventional electrostatic recording apparatus, although the printing paper must be cut at a suitable length, sooner or later due to the characteristic of the paper feeding mechanism, said paper is fed or supplied at a constant speed without being cut, until the electrostatic charge image is provided and has been developed and fixed. After the developing and fixing process, the paper is cut. In such known apparatus, the paper must be supplied at the minimum speed during the provision of the electrostatic charge image, so that the developing and fixing process, which could be undertaken at a higher speed, is actually restricted to the minimum speed. This lengthens the period of time required for the operation of the apparatus, before the produced record may be read out by an attendant, although a high speed electrostatic recording system is utilized. In the known apparatus, the contents recorded in the recording part of the system cannot be read out by an attendant prior to the completion of the next-succeeding printing of the next-succeeding printing part. In the event that there is no next-succeeding printing part, the printing paper has a blank portion equal in length to the distance between the printing part and the cutting line, and such printing paper is removed at the final stage of the operation, resulting in a waste of paper.

The principal object of my invention is to provide new and improved electrostatic recording apparatus.

An object of the invention is to provide electrostatic record ing apparatus which overcomes the disadvantages of known electrostatic recording apparatus.

An object of the invention is to provide electrostatic recording apparatus which functions at high speed in a minimum period of time.

An object of the invention is to provide electrostatic recording apparatus which functions economically and without waste.

An object of my invention is to provide electrostatic recording apparatus which functions at high speed, without waste, with efficiency, effectiveness and reliability, and is of simple structure.

In accordance with the invention, electrostatic recording apparatus for electrostatic printing on a continuous sheet of recording paper comprises electrostatic recording means for recording information on recording paper. Paper supply means supplies a continuous sheet of recording paper to the recording means. Developing and fixing means develops and fixes the recorded information on the recording paper. Cutting means cuts the recording paper after it passes through the recording means and supplies the recording paper having recorded information thereon to the developing and fixing means. Control means coupled to the recording means, the developing and fixing means, the paper supply means and the cutting means, drives the recording means at one speed and simultaneously drives the developing and fixing means at a different speed.

The control means drives the recording means at a specific low speed and simultaneously drives the developing and fixing means at a specific high speed. The control means comprises a drive motor and gear and clutch arrangements coupling the drive motor to the recording means and to the developing and fixing means.

In accordance with my invention, a method of electrostatic recording on a continuous sheet of recording paper comprises recording information on a continuous sheet of recording paper. The recording paper is cut afier the information has been recorded thereon. The recorded information on the recording paper is developed and fixed. The recording is completed at one speed and the developing and fixing is simultaneously completed at a different speed.

The recording is completed at a specific low speed and the developing and fixing is simultaneously completed at a specific high speed.

It is thus seen that I make use of the fact that, generally, the period of time required for developing and fixing is shorter than the period of time required for providing the electrostatic charge image. I therefore position the cutter between the recording apparatus and the developing and fixing apparatus, and upon the completion of the recording information, the paper is supplied or fed for the length of a blank part for recording and is then cut by the cutter. Only the cut paper, having the electrostatic charge image recorded thereon, is then supplied at high speed to the developing and fixing apparatus. This permits the record to be read by an attendant immediately upon the termination of printing. The driving roller is controlled so that the next-successive printing operation may be performed simultaneously with the high speed supply of the cut printed part.

In order that the invention may be readily carried into effect, it will now be described with reference to the accompanying drawings, wherein:

FIG. 1 is a schematic diagram of an embodiment of the electrostatic recording apparatus of the invention;

FIG. 2 is a schematic diagram of control apparatus for the electrostatic recording apparatus of FIG. 1;

FIG. 3 is a schematic diagram of an embodiment of the control apparatus of FIG. 2; and

FIG. 4 is a graphical presentation, provided adjacent a schematic indication, of the time factors in the control of the electrostatic recording apparatus of FIG. 1.

In the FIGS., the same components are identified by the same reference numerals.

In FIG. 1, the electrostatic recording apparatus of the invention comprises a paper supplying part, a recording part, a cutting part, a developing part, a fixing part, and a paper feeding part. Recording paper 1 is wound on a paper core to form a roll of such recording paper. The recording paper is guided by a supply roller 2 and a pinch roller 3. The supply roller 2 is rotated about its axis in accordance with the position of a tension roller 4. The positioning of the tension roller 4 provides a control, in a known manner, which maintains a constant length of the recording paper between a guide roller 6 and the supply roller 2.

A tension spring 5 applies a constant force to the tension roller 4. A guide roller 7 positions the recording surface of the recording paper so that it coincides with the recording surface of the recording head. A series-positioned electrode 8 produces the electrostatic charge image on the recording paper 1 and a counterelectrode 9 is positioned opposite said series-positioned electrode. The recording paper 1 runs between a paper feeding roller 10 and a pinch roller 11. A recording voltage is applied to the series-positioned electrode 8 and the counterelectrode 9 in synchronism with the feeding or supplying speed of the paper feeding roller 10 and the pinch roller 11. The recording voltage results in the production of the designated image on the recording paper 1.

The pinch roller 11 is ordinarily separated from the paper feeding roller 10 by a tension spring 13 and a lever 12 upon which said spring applies pressure. The pinch roller 1 l is moved into abutment with the paper feeding roller 10 by the action of an attractive magnet 14, when the image is recorded. A fixed cutter 15 and a movable cutter 16 function to cut the recording paper I, after the recording operation, by rapid movement toward and away from said recording paper.

The magnetic brush roller 17 develops the electrostatic charge image on the cut recording paper having the image recorded thereon. Developer or developing material 20 is supplied to the electrostatic charge image by a splash roller 18 and a clearing plate 19. A clearing roller 21, when rotated about its axis, varies the radius of the magnetic brush of the magnetic brush roller 17 and controls the supply of the developer 20 so that said developer comes into contact with the recording paper only when it is desired to develop said recording paper.

The developer 20, as is well known, comprises a carrier and a toner. Since the toner is affixed to the recording paper, however, a supplemental toner 22 is provided separately and a supplemental roller 23 is rotated synchronously with the clearing roller 21. On the other hand, developer 20 on the magnetic brush roller 17, which has completed the developing process, is cleared by a clearing plate 24 and is affixed to the supplemental roller 23 to supplement the developer supplied by the main source thereof.

A pair of fixing heaters 25 and 26 are shielded by a shielding plate 27. A paper feeding belt 28 bypasses the developing part of the apparatus. The recording paper is supplied or fed by being held or clamped between the paper feeding belt 28 and a feeding roller 29, which is provided in opposition to said belt. The paper feeding belt 28 comprises stainless steel. Guide rollers 30, 31 and 32 are provided for the paper feeding belt 28. Sprocket wheel guide rollers 33 and 34 guide the belt 28. A tension roller 35 applies tension to the belt 28.

The paper feeding belt 28 is driven or moved by a sprocket wheel 36. A feed roller 37 guides the belt 28 and a pinch roller 38 abuts said belt at the feed roller 37. Fixing heaters 39 and 40 are covered by a reflecting plate 41 and said fixing heaters and plate are ordinarily shielded by a shutter 42. An attractive feed belt 43 attracts the recording paper by air pressure produced by a vacuum chamber 46. The attractive belt 43 has a feed roller W41 and a guide roller 46. A paper feeding roller 47 and a pinch roller 48 feed or supply the recording paper 1 to the outside upon the termination of operations. In the illustration of FIG. I, the recording paper 1 terminates at the point where it is cut by the cutter 15.

When the apparatus is instructed or commanded to commence recording, the paper feeding roller rotates about its axis and commences to feed or supply the recording paper 1. Synchronously with the feeding of the recording paper 1, a recording voltage is applied to the electrodes 8 and 9, thereby providing the designated image on said recording paper. The end of the recording paper 1 is then inserted between the feed roller 37 and the pinch roller 38 and said paper is supplied to the developing part of the apparatus by the paper feeding belt 28 and the feed roller 29.

When the latent image on the recording paper reaches a position opposite the magnetic brush holder 17, the clearing roller 21 is rotated so that the radial length of the magnetic brush of the magnetic brush holder 17 is increased, and the image on the recording paper is developed. Upon completion of the developing process, the recording paper 1 is fed to the fixing part of the apparatus and is fixed by the fixing heaters 25 and 26. Upon completion of the recording operation by the recording part of the apparatus, paper feed or supply is halted and is then resumed at high speed. The paper is fed or supplied by a length equivalent to the blank part thereon, that is, by the distance between the rollers 37 and 38 and the rollers 10 and 1 1. The recording paper 1 is then halted in its movement and is cut by the removable cutter 16.

The recording paper I wound on the initial supply roller cannot then be supplied at high speed, due to the inertia of the roller. The recording paper 1 is thus provided in a constant length by the tension arm 4. The shutter 42 is then opened and the feed roller 37, the sprocket wheel 36 and the feed rollers W41 and 47 are simultaneously rotated at high speed, and the developing and fixing processes are performed. After the recording paper 1 has passed under the fixing heater 40, the shutter 42 is closed.

FIG. 2 illustrates the driving arrangement for the paper feeding part of the electrostatic recording apparatus of the invention. A motor M201 is the basic driving motor for the entire system. A first driving system x operates at low speed and a second driving speed y operates at high speed. The motor M201 constantly rotates and is coupled to a gear W1 via a first operating clutch CL206 and a gear train GT1. Microswitch groups MSW205, MSW206, MSW207 and MSW208 are operated in succession by the rotation of the gear W1. That is, the gear W1 drives the microswitch groups MSW205 to MSW208 in succession.

The microswitch groups MSW205 to MSW208 comprise a time control system for controlling the entire electrostatic recording apparatus. The microswitch groups MSW205. to MSW208 are connected to the gear W1 via clutches CL207, CL208, CL209 and CL210, respectively. Only the microswitch group MSW205 is switched to the circuit by the rotation of a code wheel DP201. The microswitch group MSW206 comprises microswitches 209 to 212. The microswitch group MSW207 comprises microswitches 213 and 214. The microswitch group MSW208 comprises microswitches 215 to 217. The microswitch groups MSW206, MSW207 and MSW208 are switched into the circuit by the rotation of the gear W1.

The time control of the entire electrostatic recording apparatus of my invention is controlled by the rotation of the gear W1. Thus, for example, the microswitch group MSW206 switches between the clutches CL201, CL203, CL202, CL205, that is, said microswitch group controls the switching time between the low speed and the high speed of the paper feeding rollers and the paper feeding belt (FIG. 1), in accordance with the time relation illustrated in FIG. 4. The microswitch group MSW207 controls the timing of the part of the electrostatic recording apparatus of the invention, which is not shown in FIG. 2, and which functions to laterally feed a plurality of printing or recording papers in parallel from the paper feeding rollers 47 and 48, and to bind such papers.

Themicroswitch group MSW205, which is provided with the code wheel DP201, controls the interval between the printing lines on the recording paper. When the instruction or command to commence the printing operation is given, the clutch CL206 engages and continues to engage until the instruction or command to terminate the recording or printing operation is given. The control of the time by the gear W1 is thus continuous during the operation of the electrostatic recording apparatus.

The clutch CL201 is provided with a brake BR201, and is engaged by the time control of the microswitch group MSW206. Consequently, a gear W2 commences to rotate at a low speed or a first speed. The paper feeding roller 10 (FIG. 1) is controlled by the gear W2. In succession, the clutch CL202 is engaged under the control of the microswitch group MSW206 and commences to rotate a gear W3 at a low speed or first speed.

The sprocket wheel 36, the paper feeding roller 37 and the feed roller 29 are controlled via the gear W3, a gear W4 and a gear arrangement Wn. The clutch CL203 is then engaged by the microswitch group MSW206 and commences to rotate the gear W4 at low speed in the low speed system x. The rotation of the gear W4 rotates the attractive paper feeding belt 46 and the paper feeding roller 47 via another clutch CL204 and the gear arrangement Wn. The recording or printing paper is thus first moved through the entire driving system at a low speed or first speed.

If the instruction or command to commence recording or printing is provided by, for example, a computer, or the like, under the foregoing circumstances, a desired one of a plurality of pinch rollers 11T, 11M and 11B is operated and commences to move the desired recording or printing papers, and recording is undertaken. In the time relation diagram of FIG. 4, the abscissa represents the time and the ordinate represents the printing interval. The first printing interval a to c, the second printing interval h to j and the third printing interval 0 to q correspond to the foregoing operations.

First, the recording or printing paper is stopped at the cutter 15 (FIG. 1), as shown by a, h and 0. The recording paper is therefore started in its movement by the paper feeding roller (FIG. 1) at a low speed, which is the first speed, and is fed from the developing part of the apparatus to the fixing part thereof. When the command or instruction to terminate the recording or printing operation is provided by, for example, the computer, the entire recording apparatus is switched to a high speed, which is the second speed. That is, when the operation reaches the point e of FIG. 4, the clutch CL201 (FIG. 2) is disengaged and the clutch CL205 (FIG. 2) engages, and each of the gears W2, W3 and W4 (FIG. 2) is rotated at the high speed in the high speed system y (FIG. 2).

When the recording paper is fed, supplied or moved for a constant period of time, and the point e, l or s in the operation is reached, the paper is stopped in its movement and its end is cut. The constant period of time is controlled by the microswitch group MSW206 of the time control system. At the point e, l or s of the operation, the recording paper is cut and is then fed, supplied or moved again at a high speed. The clutch CL202 is disengaged, however, and the clutch CLI is caused to engage, so that only the gear W2 (FIG. 2) may rotate at the low or first speed.

In other words, only the paper feeding roller 10 (FIG. 1) rotates at a low speed, so that the next recording or printing operation may be performed in succession. This is the crux of my invention. On one hand, the previously processed recording paper is fed forward at a high speed, as indicated by f, m and t of FIG. 4, and, on the other hand, simultaneously with the feeding of the recording paper, the next-succeeding recording operation is performed at a low speed, as shown in b, i and p of FIG. 4.

In the time relation diagram of FIG. 4, a high speed feeding period f is simultaneous with the next-succeeding printing period i. The instant of commencement of recording or printing in the next-succeeding recording period is h. While the recording paper cut at the termination of the next-succeeding recording or printing period is fed at high speed and is passing through the developing and fixing parts of the apparatus during the period f, the electrostatic charge image is produced during the period t. The shutter 42 (FIG. 1) of the fixing pan of the apparatus is closed during the high speed feeding of the recording paper and is opened during the low speed feeding of said paper.

FIG. 3 is a schematic diagram of an embodiment of the control apparatus of FIG. 2. FIG. 3 thus illustrates an actual arrangement for the control apparatus.

In accordance with the invention, the recording paper on which the electrostatic charge image is to be provided is separated from the recording paper on which the electrostatic charge image is to be developed and fixed after completion of the electrostatic recording operation. Therefore, only the recording paper which is to be developed and fixed may be independently fed at high speed. Furthermore, the next-succeeding recording operation may be performed simultaneously with the perfonnance of the developing and fixing operation, so that the period of time required between the input of the signal and the actual readout of the recorded information by an attendant may be considerably decreased. My invention is particularly applicable to a system for recording or printing Chinese characters by the utilization of a seriespositioned pin electrode, wherein the time required for developing and fixing is very short compared to the time required for electrostatic recording.

While the invention has been described by means of a specific example and in a specific embodiment, I do not wish to be limited thereto, for obvious modifications will occur to those skilled in the art without departing from the spirit and scope of the invention.

I claim:

1. Electrostatic recording apparatus for electrostatic printing on a continuous sheet of recording paper, said apparatus comprising a recording electrode for recording information on a continuous sheet of recording paper; first means for feeding a continuous sheet of recording paper past said recording electrode at high and low speeds;

developing and fixing means for developing and fixing electrostatic latent images imparted to a continuous sheet of recording paper by said recording electrode;

second means for feeding a continuous sheet of recording paper past said developing and fixing means at said high and low speeds; and

a cutter disposed between said recording electrode and said developing and fixing means and arranged to sever the continuous sheet of recording paper, said first and second means being independently controllable so that said first means can feed a continuous sheet of recording paper at said low speed while said second means feeds the continuous sheet of recording paper severed from the last-mentioned sheet of recording paper at high speed.

2. Electrostatic recording apparatus as claimed in claim 1, wherein said first and second means are arranged to operate at the same speed when an unsevered continuous sheet of recording paper is entrained by both said first and second means. 

1. Electrostatic recording apparatus for electrostatic printing on a continuous sheet of recording paper, said apparatus comprising a recording electrode for recording information on a continuous sheet of recording paper; first means for feeding a continuous sheet of recording paper past said recording electrode at high and low speeds; developing and fixing means for developing and fixing electrostatic latent images imparted to a continuous sheet of recording paper by said recording electrode; second means for feeding a continuous sheet of recording paper past said developing and fixing means at said high and low speeds; and a cutter disposed between said recording electrode and said developing and fixing means and arranged to sever the continuous sheet of recording paper, said first and second means being independently controllable so that said first means can feed a continuous sheet of recording paper at said low speed while said second means feeds the continuous sheet of recording paper severed from the last-mentioned sheet of recording paper at high speed.
 2. Electrostatic recording apparatus as claimed in claim 1, wherein said first and second means are arranged to operate at the same speed when an unsevered continuous sheet of recording paper is entrained by both said first and second means. 